1. Field of the invention
The present invention relates to a method of automatically inserting a printing paper in an automatic paper feeder mounted on a printer for automatically feeding the printing paper.
2. Description of the Prior Art
An automatic paper feeder of this type is disclosed for example in U.S. Pat. No. 4,529,189. The automatic paper feeder consists of a hopper for taking a cut sheet among a plurality of cut sheets accumulated on a sheet guide, a paper feed guide for guiding the cut sheet so taken out to a platen of a printer, and a stacker for discharging and accumulating cut sheets each having character data printed thereon by a printer.
The operation of feeding a paper sheet in the automatic paper feeder described above is as follows.
Paper sheets are first taken out one at a time based on a signal to instruct the paper sheet to be inserted. The cut sheet so taken out is forced to pass through the paper feed guide and wound around the platen forwardly from the rear lower portion thereof. In addition, the cut sheet is, after subjected to printing by a printing head of the printer, fed from the front upper part of the platen to the stacker.
Furthermore, U.S. Pat. No. 4,326,815 is also known wherein an automatic paper feeder of the type described above consists of a printing paper tray, a drive roller for taking out a printing paper from the tray, a paper feed path, two sensors provided on the paper feed path and a hopper composed of a deflector plate and an exit guide plate.
The paper feeder described above effcts the following operations of feeding a printing paper. According to the first operation, the drive roller is first rotated to take out the printing paper from the paper tray. The paper so taken out is guided to the paper feed path and conveyed toward the platen of the printer. After detecting the top end of the printing paper by the first sensor, the platen is rotated to furthermore convey the paper until the top end thereof is detected by the second sensor to permit the printing paper to be stopped. Thereafter, character data is printed on the printing paper by the printing head. After the printing is finished, the paper printed as described above is conveyed to the hopper.
According to the second operation, with an upper tray switch and a lower tray switch being depressed, the printing head is positioned at the center of the printer, and the automatic paper feeder is placed in an envelope/single sheet mode. An envelope or single sheet is inserted into an input slot formed between a deflector plate and an exit guide plate. Thereafter, turning a platen knob, the printing paper is set to a prescribed position.